Dissecting antibiosis and antixenosis mechanisms conferring resistance to C. chinensis in chickpea

Pulse beetle, Callosobruchus chinensis (L.), is a serious storage pest of chickpea causing extensive grain damage and percent weight loss. The present study evaluated the resistance of different chickpea genotypes to C. chinensis by assessing antibiosis and antixenosis mechanisms under laboratory conditions. Antibiosis was studied using parameters such as adult emergence, number of holes per grain, percentage of adult emergence, seed weight loss, growth index, and adult weight. Significant differences were observed among the genotypes. PI 599066 exhibited complete resistance, as no adult emergence, seed damage, or weight loss was recorded. Genotypes IG 72953 and IG 72933 showed high levels of resistance with reduced adult emergence, minimal grain damage, lower adult emergence percentage, and lighter adults, indicating strong antibiosis effects. In contrast, ICCV 2, KAK 2, VIHAR, and JGK 2 were highly susceptible and supported greater insect development and damage. Antixenosis studies revealed significant variation in adult preference, with minimum attraction observed in IG 72953 and maximum preference in ICCV 2. The results indicate that resistance to C. chinensis in chickpea is mediated through both antibiosis and antixenosis mechanisms. The resistant genotypes identified can be effectively utilized in breeding programmes aimed at improving post-harvest pest resistance in chickpea.